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一次性餐具里增加增塑劑的性能研究!

一次性餐具里增加增塑劑的性能研究!

網(wǎng)址:http://www.fs-sjg.com 手機(jī)頁面二維碼 2021-07-14 11:37:00    

近年來,不同類型的全淀粉能降解生物材料受到了市場內(nèi)外研究者的青睞,全淀粉能降解材料通常指的是淀粉含量高于80%加工制備而成的材料,里面所添加的加強(qiáng)劑、增塑劑等也可整體降解,其中的一次性玉米淀粉餐具廢棄后能夠在較短的時間內(nèi)被士壤或水域中存在的微生物、酸、堿等透徹分解,其產(chǎn)物為二氧化碳和水,是一種環(huán)境友好型材料。
In recent years, different types of all starch degradable biomaterials have been favored by researchers at home and abroad. All starch degradable materials usually refer to the materials prepared by processing with starch content higher than 80%. The reinforcing agent and plasticizer added in them can also be degraded as a whole, The disposable corn starch tableware can be thoroughly decomposed by microorganisms, acids and alkalis in soil or water in a short time after being discarded. The products are carbon dioxide and water, which is a kind of environment-friendly material.
有研究報導(dǎo),增塑劑的添加可由不同角度影響熱塑性淀粉的機(jī)械性能,一方面其可增加餐具的塑化程度,另一方面可促使鏈結(jié)構(gòu)的重排,增進(jìn)其硬度。除此之外,淀粉分子鏈的構(gòu)成、大小及構(gòu)象等也會對熱塑性淀粉的制備產(chǎn)生影響。
It has been reported that the addition of plasticizer can affect the mechanical properties of thermoplastic starch from different angles. On the one hand, it can increase the plasticization degree of tableware, on the other hand, it can promote the rearrangement of chain structure and improve its hardness. In addition, the composition, size and conformation of starch molecular chain also affect the preparation of thermoplastic starch.
有研究探討了淀粉的結(jié)晶結(jié)構(gòu)及分子量大小對其材料拉伸強(qiáng)度、斷裂伸長率和可塑性能的影響,表面淀粉相對結(jié)晶度、結(jié)晶構(gòu)形的轉(zhuǎn)變并不會影響其力學(xué)性能,但其直鏈/支鏈比與分子量卻可以顯明影響所制備玉米淀粉餐具的相關(guān)性能。還有研究同樣表明,直鏈含量的增加利于材料強(qiáng)度、硬度及溶體黏度的增進(jìn),且越容易出現(xiàn)剪切變稀現(xiàn)象。
The effects of crystal structure and molecular weight of starch on tensile strength, elongation at break and plasticity were studied. The changes of relative crystallinity and crystal structure of surface starch did not affect its mechanical properties, but the amylose / amylopectin ratio and molecular weight could significantly affect the related properties of the prepared corn starch tableware. Other studies also show that the increase of linear chain content is conducive to the improvement of material strength, hardness and solution viscosity, and the shear thinning phenomenon is more likely to occur.
                                     一次性玉米淀粉餐具
一次性玉米淀粉餐具大多以甘油作為增塑劑,但由于淀粉分子鏈間或內(nèi)部的重排,致使熱塑性淀粉材料在儲存的過程中容易產(chǎn)生重排、聚集等回生現(xiàn)象,從而導(dǎo)致材料老化變脆,減低或失去其應(yīng)用價值。
Most disposable corn starch tableware uses glycerin as plasticizer. However, due to the rearrangement of starch molecular chain or internal chain, it is easy for thermoplastic starch materials to have the phenomena of rearrangement and aggregation during storage, which leads to the aging and brittleness of materials and reduces or loses its application value.
研究者為了改變相關(guān)缺陷做了相關(guān)研究,其中有人采用尿素、硫脲和鹽酸胍等胺基類化合物作為增塑劑發(fā)現(xiàn),此類增塑劑既可促使淀粉糊化行為的發(fā)生,又可制約淀粉基餐具性能的劣變。還有人通過酶解原淀粉制備納米淀粉微晶,繼而米將納米淀粉微晶在甘油醇的作用下制備一次性玉米淀粉餐具,結(jié)果發(fā)現(xiàn)粒子內(nèi)部及顆粒與粒子間能夠形成較強(qiáng)的氫鍵,體系間相互作用增加,從而致使玉米淀粉餐具的整體性能有所改良。與此同時,淀粉較小晶體的存在還能夠減緩玉米淀粉在高水分條件下的老化程度。
In order to change the related defects, researchers have done related research, some of them use amino compounds such as urea, thiourea and guanidine hydrochloride as plasticizers, and found that such plasticizers can not only promote the occurrence of starch gelatinization behavior, but also restrict the deterioration of starch based tableware performance. Others prepared nano starch microcrystals by enzymolysis of raw starch, and then prepared disposable corn starch tableware with nano starch microcrystals under the action of glycerol alcohol. The results showed that strong hydrogen bonds could be formed inside and between particles, and the interaction between systems increased, which improved the overall performance of corn starch tableware. At the same time, the existence of smaller starch crystals can also slow down the aging degree of corn starch under high moisture conditions.